Incorrect bitwise calculation/combination? 'WebSocketFrame.ToArray()'

I get the feeling that the following code line might be faulty:

int num = ((int) ((byte) ((int) ((byte) ((int) ((byte) ((int) ((byte) ((int) ((byte) ((int) this._fin << 1) + this._rsv1) << 1) + this._rsv2) << 1) + this._rsv3) << 4) + this._opcode) << 1) + this._mask) << 7) + (int) this._payloadLength;

And should possibly be replaced with something like this:

int num = ((byte)_fin << 15) + ((byte)_rsv1 << 14) + ((byte)_rsv2 << 13) + ((byte)_rsv3 << 12) + ((byte)_opcode << 8) + ((byte)_mask << 7) + (_payloadLength);

For the '1.0.3-rc11' version (- '1.0.2.59611'?).

Also, is the repo' for the RC version available to the public?

At least it appeared to be the case on the receiving end, and during transit (as seen via Wireshark), as the 'FIN' flag seemed unset upon arrival; although I had converted the DLL to C# code (- was something inadvertently adjusted/lost in the translation?).

Start at WebSocketFrame.ToArray() and inspect the reported bitwise calculation against the WebSocket frame header layout. Reproduce serialization for a frame with FIN and the listed flags, then compare the resulting bytes with the expected header and the Wireshark observation. Done means confirming whether the implementation or the C# translation causes the incorrect FIN flag and documenting the result.